The Swiss franc fell against the dollar and the euro amid speculation the Swiss National Bank may tighten its target to limit the currency’s strength. Swiss central bank spokesman Walter Meier in Zurich declined to comment when asked about speculation that policy makers may adjust the franc ceiling against the euro. The franc weakened 0.6 percent to 1.2142 per euro at 10:24 a.m. in New York. It fell 0.6 percent to 88.77 centimes per U.S. dollar.The dollar rallied and Treasuries erased their decline after the International Monetary Fund predicted severe global growth repercussions if Europe fails to contain the sovereign debt crisis. IMF said the European Central Bank should lower interest rates if risks to growth persist. The ECB’s current benchmark rate is 1.5 percent. The euro was little changed at $1.3682. The shared currency traded at 104.77 yen, from 1.0482 yesterday, when it reached 103.96 yen, almost the least since 2001. German investor confidence fell to the lowest in more than 2 1/2 years in September as Europe’s debt crisis and a global slowdown damped the outlook for growth. Australia’s dollar was the biggest winner against the U.S. currency, rising 0.6 percent to $1.0280.